basic_ostream::sentry
The nested class describes an object whose declaration structures the formatted output functions and the unformatted output functions.
class sentry {
public:
explicit sentry( basic_ostream<_Elem, _Tr>& _Ostr );
operator bool( ) const;
~sentry( );
};
Remarks
The nested class describes an object whose declaration structures the formatted output functions and the unformatted output functions. If ostr.good is true and ostr.tie is not a null pointer, the constructor calls ostr.tie->flush. The constructor then stores the value returned by ostr.good in status. A later call to operator bool delivers this stored value.
If uncaught_exception returns false and flags & unitbuf is nonzero, the destructor calls flush.
Requirements
Header: <ostream>
Namespace: std